Channel mounted activating mechanism for an endoscopic ligator

ABSTRACT

An activating mechanism (20) for activating an endoscopic ligator is disclosed. The activating mechanism (20) includes a mounting component (21) and an activating component (22) coupled thereto. The mounting component (21) inserts directly into the proximal opening of an operating channel of an endoscope and is dimensioned to fit within the operating channel to mount the mechanism (20) to the endoscope. The mounting component (21) includes a channel receiving an activation line of the ligating device which is threaded through the operating channel and the channel in the mounting component, and onto the activating component (22) of the activating mechanism (20). The activation line attaches to a spool (50) of the activating component (22). The activating component (22) further provides a drive pin (40) and a roller clutch (70) for setting the activating component (22) in an engaged or disengaged position and a knob (60) for rotating the drive pin (40). When the drive pin (40) is engaged with the roller clutch (70), the knob (60) can only rotate in one direction. When the drive pin (40) is in the disengaged position from the roller clutch (70), the knob (60) can rotate in either direction.

This application is a continuation application of application Ser. No.08/524,069 filed Sep. 6, 1995. Now U.S. Pat. No. 5,735,861.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to the field of endoscopic ligation. Moreparticularly, the invention relates to devices which are used toactivate an endoscopic ligator for ligating lesions within a holloworgan of the body.

2. Background

Endoscopic ligating devices which apply elastic rings over selected bodytissue are well known in the prior art. The ligating device is typicallyactivated by retracting a line (string, wire, or cable) that is attachedto a ligator disposed at the distal or insertion end of an endoscope.The line is threaded through a working or operating channel of theendoscope to the proximal end of the instrument. In some prior devices,the ligator can be activated by manually pulling on the activating line.In other devices, mechanically assisted operation is provided by meansof a hand operated reel or trigger, or a motor drive mechanism.

Pre-existing activating mechanisms have generally not been securelymountable to the endoscope, or easily and securely attachable tovariously configured endoscopes, have not operated with satisfactorycontrol and accuracy, and have been difficult to disconnect. Wherefore,there is a need for a new activating mechanism which overcomes theseshortcomings of prior activating mechanisms.

SUMMARY OF THE INVENTION

The present invention provides a new and unique activating mechanism foran endoscopic ligator which mounts to a variety of endoscopes andoperates to provide precise control to effectuate ligation. The deviceis easy and convenient to use, and can be simply disconnected when theligation procedure has been completed.

In one embodiment, an activating mechanism mounts to an endoscope bymeans of a mounting component which is inserted directly into a port ofthe endoscope. In this way, the activating mechanism can be securely andsimply mounted to the endoscope with a single motion. In one specificembodiment, a mounting component is adapted to be fitted within anoperating or working channel and/or within the operating channel'ssealing port for a wide variety of endoscopes. In this manner, thesecure attachment of the activating mechanism is simply accomplished forthe ligating procedure to be conducted, and the mechanism can also bereadily removed after the ligation has been performed.

In another aspect of the invention, there is further provided means foractivating the ligating device which is precisely controllable and whichcan be simply disconnected upon the completion of the ligationprocedure. In one embodiment, an activating component operates in aworking mode in which the activation line can be retracted underprecisely controlled tension to release the ligating bands as desired.When the procedure is suspended or completed, the activating componentcan be switched to a disengaged mode in which tension on the activationline is released to prevent unintended band release and to allow foreasy disconnection of the activation line from the activating component.

It is an object of the present invention to provide an activatingmechanism for an endoscopic ligator which easily mounts to an endoscopein a stable fashion. It is a further object of the present invention toprovide an activating mechanism for an endoscope which can be securelymounted within a channel or auxiliary port of an endoscope.

It is a further object of the present invention to provide an activatingmechanism for an endoscopic ligator which is precisely controllable toeffectuate endoscopic ligation as desired. Yet another object is toprovide such an activating mechanism which is convenient to use andwhich can be readily disconnected at the completion of the procedure.

These and other objects and advantages of the present invention will beapparent from a review of the following description of the preferredembodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal fragmented view of an endoscope with anendoscopic ligator (generally shown) that is located at the distal endof the endoscope.

FIG. 1A is a cross-sectional view of a first configuration of a proximalchannel portion of an operating channel of the endoscope of FIG. 1.

FIG. 1B is a cross-sectional view of a second configuration of theproximal channel portion of an operating channel of the endoscope ofFIG. 1.

FIG. 1C is a cross-sectional view of a third configuration of theproximal channel portion of an operating channel of the endoscope ofFIG. 1.

FIG. 2 is a top plan view of an activating mechanism for activating theendoscopic ligator of FIG. 1.

FIGS. 3A-3C are views of a mounting component of the activatingmechanism of FIG. 2.

FIGS. 4A-4E are views of a base of the activating mechanism of FIG. 2.

FIGS. 5A-5C are views of a drive pin of the activating mechanism of FIG.2.

FIGS. 6A-6B are views of a spool of the activating mechanism of FIG. 2.

FIG. 7 is a view of a knob of the activating mechanism of FIG. 2.

FIGS. 8A-8B are views of a disengaged mode of operation of theactivating mechanism of FIG. 2 wherein knob 60 is free to rotate ineither direction (A or B).

FIGS. 9A-9B are views of a working mode of operation of the activatingmechanism of FIG. 2 wherein knob 60 is only free to rotate in a singledirection.

FIG. 10A is a view of the activating mechanism of FIG. 2 prior toinsertion into the proximal channel portion of FIG. 1A.

FIG. 10B is a view of the activating mechanism of FIG. 2 prior toinsertion into the proximal channel portion of FIG. 1C.

FIG. 10C is a view of the activating mechanism of FIG. 2 prior toinsertion into the proximal channel portion of FIG. 1C.

FIG. 11A is a view of the activating mechanism of FIG. 2 after insertioninto the proximal channel portion of FIG. 1A.

FIG. 11B is a view of the activating mechanism of FIG. 2 after insertioninto the proximal channel portion of FIG. 1B.

FIG. 11C is a view of the activating mechanism of FIG. 2 after insertioninto the proximal channel portion of FIG. 1C.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiment illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications in the illustrated device, and such further applicationsof the principles of the invention as illustrated therein beingcontemplated as would normally occur to one skilled in the art to whichthe invention relates.

Referring more particularly to the drawings, there is shown in FIG. 1endoscope 10a with endoscopic ligator 14 attached to the distal orinsertion end of endoscope 10a. Endoscopic ligator 14 is generally shownin FIG. 1. A more detailed description of one type of ligator 14 isshown in pending U.S. application Ser. No. 08/260,380 filed on Jun. 14,1994. Specific reference is made to FIGS. 16-20 and descriptions thereofin the '380 Application, which disclosure is hereby incorporated byreference. The specification in co-pending U.S. application Ser. No.08/709423, filed on Sep. 6, 1996 as a continuation-in-part of of theabove application Ser. No. 08/260,380 and entitled Endoscopic LigatingApparatus is incorporated herein by reference as well. In general terms,ligator 14 carries a number of ligation bands that can be individuallyor collectively released from the ligator around a subject tissue. Thepresent invention can also be adapted for use with other ligators, suchas the instrument in U.S. Pat. No. 5,320,630.

Endoscope 10a can be a conventional endoscope with an operating controlportion 11a, a flexible section 12a, and a distal or insertion endportion 13a. Endoscopic ligator 14 is located at distal end portion 13aof endoscope 10a and includes an activation line 15. Endoscope 10a alsoincludes an operating or working channel 16a which extends throughendoscope 10a from distal end portion 13a to operating control portion11a and to proximal opening 18a. Activation line 15 is preferablythreaded from ligator 14 through operating channel 16a and exits throughproximal opening 18a.

Referring still to FIG. 1, operating channel 16a includes a proximalchannel portion 19a at the proximal opening 18a, which can beconstructed in a variety of configurations. For example, FIGS. 1A, 1Band 1C are cross-sectional views of proximal channel portions 19a, 19band 19c, respectively, each proximal channel portion having a differentconfiguration. FIG. 1A shows endoscope 10a which is similar to a type ofcommercial endoscope generally sold by Pentax. FIG. 1B shows endoscope10b which is similar to a type of commercial endoscope generally sold byOlympus. FIG. 1C shows endoscope 10c which is similar to a type ofcommercial endoscope generally sold by Fujinon. These endoscopes includesealing members 17a-c, respectively, mounted at the correspondingproximal channel portions 19a-c.

FIG. 2 is a top plan view of an activating mechanism 20 according to oneembodiment of the present invention. Activating mechanism 20 includesmounting component 21 and activating component 22. Activating component22 can include base 30, drive pin 40, spool 50, knob 60, roller clutch70 (see FIG. 4B), and retaining cap 90. Mounting component 21 attachesto activating component 22 and is used to mount activating mechanism 20to proximal channel portions 19a, 19b, 19c, or to other auxiliary portor proximal channel portion configurations of other endoscopes.

FIG. 3A is a view of a first embodiment of mounting component 21.Mounting component 21 includes coupling portion 23, first mating portion24a, second mating portion 24b and outer sealing portion 25. Couplingportion 23 is adapted to be connected to activating component 22.Coupling portion 23, for example, can be threaded, or press-fit into, orintegral with activating component 22.

The first, second and third mating portions 24a-c, respectively, andouter sealing portion 25 of mounting component 21 are particularlyconfigured in one specific embodiment as shown in FIG. 3A. It is to beappreciated that mounting component 21 can be constructed in a varietyof alternative configurations as well in accordance with the teachingsof this invention.

The specific embodiment of the mounting component 21 shown in FIG. 3Acan be engaged to an endoscope having a proximal opening 18a andproximal channel portion 19a as shown in FIG. 1A. In the depictedendoscope 10a, a sealing member 17a is provided at the proximal channelportion. The mounting component of FIG. 3A extends into proximal channelportion 19a through proximal opening 18a and sealing member 17a. In thisspecific embodiment, first mating portion 24a is shaped to be fittedwithin proximal channel portion 19a, while the second mating portion 24bis received within sealing member 17a. In this specific embodiment, theouter sealing portion 25 is not received within the sealing member 17aor proximal channel portion 19a of the endoscope.

The fit between the mating portion 24a-b of the mounting component andthe sealing member 17a and proximal channel portion 19a of the endoscopeprovides a stable mount for the activating mechanism 20. Mountingcomponent 21 is configured to fit in a variety of ways to serve toenhance the secure mounting of the device to various endoscopes. Forexample, depending on the endoscope with which the activating mechanismis being mounted, the fit may be a form fit in which the mountingcomponent portion essentially follows the shape of the endoscope sealingmember or proximal channel portion. The fit can also be a friction or apress fit or the length of the mounting component or a portion thereof,or alternatively, the mounting component portions could fit looselywithin the endoscopic channel to provide enhanced stability by which themounting component 21 restricts or limits relative movement of theactivating mechanism 20 about the endoscopic operating channel.

The mounting component of FIG. 3A can be stably mounted to any of avariety of different endoscopes. In FIG. 1B, for example, first matingportion 24a and second mating portion 24b are sized to fit withinproximal channel portion 19b of an endoscope which is differently designthan that shown in FIG. 1A. With the same structure of the mountingcomponent, the outer sealing portion 25 can be received within thesealing member 17b of the endoscope in FIG. 1B as well as the endoscopeof FIG. 1A. As shown in further detail in FIGS. 10B and 11B, In FIG. 1B,the mating portions 24a-b are form or geometrically fitted within theproximal channel portion 19b. The outer sealing portion 25 is alsopreferably resiliently or form fitted into the sealing member 17b. Asexplained above, the mounting component portions are sized andconfigured to fit within the proximal channel portion 19b and/or sealingmember 17b of variously designed endoscopes so as to help achieve astable mounting of the device to the endoscope.

The mounting component of FIG. 3A can also be mounted, for example, toan endoscope of the type shown in FIG. 1C. Again, the fitting ofmounting component 21 within the sealing member 17c and/or proximalchannel portion 19c of the endoscope 10c can be accomplished in variousways which help to accomplish the stable mounting of activatingmechanism 20. In this specific example, it is to be noted that outersealing portion 25 is not configured to extend into the sealing member17c, as is shown by the other above examples.

Mounting component 21 also preferably provides first threading channel27 which extends through mounting component 21. First opening 28 offirst threading channel 27 is shown in FIG. 3B and an opposite secondopening 29 of first threading channel 27 is shown in FIG. 3C. Aftermounting component 21 has been inserted into a proximal channel portionconfiguration, activation line 15 can be threaded into first opening 28and out of second opening 29 for connection to activating component 22.

FIG. 4A is a frontal view of base 30 of activating component 22. Base 30can include a base portion 30a, first arm 31 connected to base portion30a, and a second arm 32 also connected to base portion 30a. While thepresent invention contemplates that the connections of first arm 31 andsecond arm 32 can exist in any form, preferably first arm 31 and secondarm 32 are integral with base portion 30a. As shown in FIG. 4B, firstarm 31 provides first receiving opening 33 and as shown in FIG. 4C,second arm 32 provides second receiving opening 34. Base portion 30adefines recess 35 located on its bottom side and second threadingchannel 36 which communicates between recess 35 and the top side of baseportion 30a. FIG. 4D is a bottom side view of FIG. 4A, and further showsrecess 35 and first opening 37 of second threading channel 36. FIG. 4Eis a top side of FIG. 4A, showing the top side of first arm 31 andsecond arm 32, and second opening 38 of second threading channel 36 withan inner sealing member 39 located therein. When activation line 15 isthreaded through mounting component 21, it is further threaded intofirst opening 37, through an inner sealing member 39 disposed withinsecond opening 38, and out of second opening 38.

FIG. 5A is a side view of drive pin 40. Drive pin 40 preferably includesfirst rotating portion 41a, second rotating portion 41b, third rotatingportion 42, and fourth rotating portion 43. Depending upon the mode ofoperation, first rotating portion 41a or second rotating portion 41b maybe disposed within roller clutch 70 (see FIG. 4b) located within firstreceiving opening 33 of first arm 31. First rotating portion 41a isdimensioned to rotate within roller clutch 70 while second rotatingportion 41b is dimensioned to engage roller clutch 70 within firstreceiving opening 33 of first arm 31 to thereby allow for rotation inonly one direction when activating component is set in its engagedworking mode. FIG. 5B is a front view of drive pin 40. First rotatingportion 41a is configured to receive retaining cap 90 located on the endof drive pin 40 (see FIG. 2). Retaining cap 90 prevents the dislodgingof first rotating portion 41a from first receiving opening 33. FIG. 5Cis a back view of drive pin 40.

Referring back to FIG. 5A, third rotating portion 42 is disposed withinsecond receiving opening 34 of second arm 32. Third rotating portion 42is designed to rotate in and slide within second receiving opening 34.Drive pin 40 further includes a knurled portion 44 in third rotatingportion 42 which connects to knob 60. Fourth rotating portion 43 isdesigned to be disposed within spool 50.

FIG. 6A is a side view of spool 50. Spool 50 can include a slot 51having a hole 52. Hole 52 and slot 51 receive activation line 15 fromsecond opening 38 of base 30. Activation line 15 is coupled to hole 52and slot 51 by slipping activation line into slot 51 and placing a knotin activation line 15 through hole 52. FIG. 6B is a front view of spool50. Spool 50 further includes drive channel 53. Drive channel 53receives third rotating portion 43 of drive pin 40 both of which canhave a square cross-sectional shape as illustrated. Spool 50 thusrotates in the same direction as drive pin 40 when the drive pin 40 isrotated by knob 60, owing to the engagement between fourth rotatingportion 43 of drive pin 40 and drive channel 53 of spool 50. It isunderstood that fourth rotating portion 43 of drive pin 40 and drivechannel 53 of spool 50 can assume a variety of configurations providedthat the spool 50 will rotate with drive pin 40.

FIG. 7 is a bottom side view of knob 60. Knob 60 includes connectingrecess 61. Connecting recess 61 connects with drive pin 40 by fittingonto knurled portion of drive pin 40 (not shown). This connectionenables knob 60 to rotate drive pin 40. The connection also preventsthird rotating portion 42 of drive pin 40 from dislodging out of secondreceiving opening 34. The present invention contemplates that knob 60can be operated either manually or mechanically.

FIGS. 8 and 9 are views of the two modes of operation for activatingmechanism 20. FIG. 8A depicts the disengaged mode of operation.Activation line 15 is threaded through mounting component 21 and base30, and is coupled to spool 50. The disengaged mode of operation isbased on a disengaged position of drive pin 40 within roller clutch 70.FIG. 8A depicts third rotating portion 42 of drive pin 40 beingsubstantially disposed outside of second arm 32. FIG. 8A further showsfirst rotating portion 41a of drive pin 40 being substantially disposedwithin first arm 31. In this position, first rotating portion 41a iswithin the one-way roller clutch 70. This is the disengaged position ofdrive pin 40. As shown in FIG. 8B, when drive pin 40 is in thedisengaged position, knob 60 can be rotated freely in either direction(A or B). After the attachment of activation line 15 to spool 50, knob60 can be rotated to wrap activation line 15 around spool 50. To unwrapactivation line 15, knob 60 can be rotated in the opposite direction ofthe first rotation.

FIG. 9A depicts the working mode of operation. The working mode ofoperation is also based on a working position of drive pin 40 withinroller clutch 70. FIG. 9A shows the second rotating portion segment 42being substantially disposed within second arm 32. FIG. 9A further showsfirst rotating portion 41a being substantially disposed outside of firstarm 31 with second rotating portion 41b in engaging contact with rollerclutch 70. As shown in FIG. 9B, when drive pin 40 is in the engagedposition, knob 60 can only be rotated in one direction due to theengagement between second rotating portion 41b and clutch 70. After theattachment of activation line 15 to spool 50, knob 60 can be rotated inone direction to wrap activation line 15 around the spool 50 undercontrolled tension to release ligating bands from ligator 14 as desired.Upon completion of the procedure, activating component 21 may be resetin the disengaged mode to release the tension from activation line 15and allow activation line 15 to be unwound from spool 50 anddisconnected therefrom.

While two modes of operation has been described herein for activatingmechanism 20, activating mechanism 20 could less desirably be usedexclusively in a working mode, with roller clutch 70 and second rotatingportion 41b being maintained in engagement. In a less preferredembodiment, roller clutch 70 could be eliminated and an element, such asa one-way clip, could be used to engage the drive pin 40, spool 50and/or knob 60 to restrict the rotation of knob in only one direction asillustrated in FIG. 9B.

FIGS. 10A and 11A show how activating mechanism 20 is mounted toendoscope 10a of FIG. 1A by inserting mounting component 21 intoproximal channel portion 19a. For this illustration, endoscope 10a isshown provided with sealing member 17a which is coupled to proximalopening 18a. FIG. 10A shows the alignment of activating mechanism 20with proximal opening 18a prior to insertion of mounting component 21therein. FIG. 11A shows mounting component 21 inserted into proximalchannel portion 19a. Upon insertion, first mating portion 24a and secondmating portion 24b can achieve the fit within proximal channel portion19a and sealing member 17a, correspondingly, as described above in orderto mount activating mechanism 20 to endoscope 10a. As previouslydescribed, activation line 15 is threaded into and attached toactivating mechanism 20.

FIGS. 10B and 11B show how activating mechanism 20 is mounted toendoscope 10b of FIG. 1B by inserting mounting component 21 intoproximal channel portion 19b. For this illustration, endoscope 10b isshown provided with sealing member 17b which is coupled to proximalopening 18a. FIG. 10B shows the alignment of activating mechanism 20with proximal opening 18b prior to insertion of mounting component 21therein. FIG. 11B shows mounting component 21 inserted into proximalchannel portion 19b. The fit between the first and second matingportions 24a-b and the proximal channel portion 19b, and between outersealing portion 25 and sealing member 17b, can be as described above inorder to mount activating mechanism 20 to endoscope 10b and outersealing portion 25 seals with sealing member 17b of endoscope 10b.

FIGS. 10C and 11C show how activating mechanism 20 is mounted toendoscope 10c of FIG. 1C by inserting mounting component 21 intoproximal channel portion 19c. For this illustration, endoscope 10c isshown provided with sealing member 17c which is coupled to proximalopening 18c. FIG. 10C shows the alignment of activating mechanism 20with proximal opening 18c prior to insertion of mounting component 21therein. FIG. 11C shows mounting component 21 inserted into proximalchannel portion 19c. Again, the fit between the mounting component 21and the proximal channel portion 19c and sealing member 17c can be asdescribed above.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiment has been shown and described and that allchanges and modifications that come within the spirit of the inventionare desired to be protected.

What is claimed is:
 1. An activating mechanism for activating anendoscopic ligator to ligate lesions within a hollow body organ, theendoscopic ligator being positioned at the distal insertion end of anendoscope, the endoscope having a channel which extends through theendoscope from an opening at the distal end to an opening at a proximalend of the endoscope, the ligator having an activation line which isthreaded through the channel of the endoscope to the proximal opening ofthe endoscope, said activating mechanism comprising:(a) a mountingcomponent, said mounting component having a first portion sized to beinserted into the proximal opening of the channel of the endoscope, saidmounting component including a threading channel extending therethroughfor threading the activation line through said mounting component whensaid first portion of said mounting component is inserted into theproximal opening of the channel of the endoscope; and (b) an activatingcomponent connected to said mounting component, said activatingcomponent includingmeans for attachment of the activation line when theactivation line is threaded through said threading channel of saidmounting component, and means for retracting the activation line whenthe activation line is attached to said activating component whereby theligating device can be activated as desired by selective retraction ofthe activation line.
 2. The activating mechanism of claim 1 in which theendoscope further includes a sealing member disposed over the proximalopening of the channel, the sealing member having an opening incommunication with the proximal opening of the endoscope, wherein:saidmounting component further includes a second portion adjacent said firstportion, said second portion sized to be received within the sealingmember opening when said first portion extends through the proximalopening of the channel.
 3. The activating mechanism of claim 2 whereinsaid second portion of said mounting component is sized to form afriction fit with the sealing member opening.
 4. The activatingmechanism of claim 1,wherein said attachment means includes a spool withmeans for engaging the proximal end of the activation line when theactivation line is threaded through said threading channel of saidmounting component; wherein said retracting means includesa knoboperationally connected to said spool for manual rotation of said spool,and a base configured to rotationally support said spool, said basedefining an opening therethrough; and wherein said mounting componentfurther includes a coupling portion sized to be received within saidopening in said base to connect said activating component to saidmounting component.
 5. The activating mechanism of claim 1,wherein saidattachment means includes a spool with means for engaging the proximalend of the activation line when the activation line is threaded throughsaid threading channel of said mounting component; and wherein saidretracting means includesa knob operationally connected to said spoolfor manual rotation of said spool, a base configured to rotationallysupport said spool, and a one-way clutch engaging said spool to preventrotation of said spool in one direction and permit rotation of saidspool in an opposite direction.
 6. The activating mechanism of claim 5,wherein said retracting means further includes a drive pin supported onsaid base to rotate and reciprocate relative to said base, said drivepin havinga first portion disposed within said spool, said first portionof said drive pin having means for imparting rotational movement fromsaid drive pin to said spool, a second portion connected to said knob, athird portion configured to engage said clutch when said drive pin is ina first position, said first position being said third portion disposedwithin said clutch, and a fourth portion adjacent said third portion,said fourth portion configured for free-wheel rotation within saidclutch when said drive pin is reciprocated to a second position, saidsecond position being said fourth position disposed within said clutch.7. An activating mechanism for activating an endoscopic ligator toligate lesions within a hollow body organ, the endoscopic ligator beingpositioned at the distal insertion end of an endoscope, the endoscopehaving a channel which extends through the endoscope from an opening atthe distal end to an opening at the proximal end of the endoscope, theligator having an activation line which is threaded through the channelof the endoscope to the proximal opening of the endoscope, saidactivating mechanism comprising:(a) a mounting component, said mountingcomponent having a first portion sized to be inserted into the proximalopening of the channel of the endoscope, said mounting componentincluding a threading channel extending therethrough for threading theactivation line through said mounting component when said first portionis inserted into the proximal opening of the channel of the endoscope;and (b) an activating component connected to said mounting component,said activating component includinga spool to engage the proximal end ofthe activation line when the activation line is threaded through saidthreading channel of said mounting component, and a knob operativelyconnected to said spool to manually rotate said spool whereby theactivation line can be selectively retracted when engaged with saidspool to activate the ligating device as desired.
 8. The activatingmechanism of claim 7 wherein said first portion of said mountingcomponent is sized to form a friction fit within the channel of theendoscope.
 9. The activating mechanism of claim 7 in which the endoscopefurther includes a sealing member disposed over the proximal opening ofthe channel, the sealing member having an opening in communication withthe proximal opening of the endoscope, wherein:said mounting componentincludes a second portion adjacent said first portion, said secondportion sized to be received within the sealing member opening when saidfirst portion extends through the proximal opening of the channel. 10.The activating mechanism of claim 9 wherein said second portion of saidmounting component is sized to form a friction fit with the sealingmember opening.
 11. The activating mechanism of claim 7,wherein saidactivating component further includes a based configured to rotationallysupport said spool, said base defining an opening therethrough; andwherein said mounting component further has a coupling portion sized tobe received within said opening in said base to connect said activatingcomponent to said mounting component.
 12. The activating mechanism ofclaim 7, wherein said activating component further includesa baseconfigured to rotationally support said spool, and a one-way clutchengaging said spool to prevent rotation of said spool in one directionand permit rotation of said spool in an opposite direction.
 13. Theactivating mechanism of claim 12, wherein said activating componentfurther includes a drive pin supported on said base to rotate andreciprocate relative to said base, said drive pin havinga first portiondisposed with said spool, said first portion of said drive pin havingmeans for imparting rotational movement of said drive pin to said spool,a second portion connected to said knob, a third portion configured toengage said clutch when said drive pin is in a first position, saidfirst position being said third portion disposed within said clutch, anda fourth portion adjacent said third portion, said fourth portionconfigured for free-wheel rotation within said clutch when said drivepin is reciprocated to a second position, said second position beingsaid fourth portion disposed within said clutch.